ABSTRACT
Objective:Recent studies have shown that in contrast to decrease in distal gastric adenocarcinoma (DGA), incidence of adenocarcinoma of the esophagogastric junction (AEG) has increased noticeably in numerous counties. However, the reasons remain unclear. This study evaluated the possible differences in the expression of KLF4, SP1, and Cyclin D1 in AEG and DGA, and explored the potential carcinogenesis of AEG. Methods:Immunohistochemistry was performed on paraffin-embedded tissues to evaluate the pu-tative differences in the expressions of KLF4, SP1, and Cyclin D1 at protein level between AEG (n=58) and DGA (n=47). The patholog-ical significance of these markers between the two groups was also compared and analyzed. Results:The percentage of positive KLF4 expression was significantly lower in DGA than in AEG (P<0.05). Lower KLF4 expression was found both in well-or moderately dif-ferentiated cases and in poorly differentiated cases with DGA compared with their AEG counterparts (P<0.05). However, positive stain-ing for SP1 was significantly higher in DGA (P<0.05). No significant difference was found in the expression of Cyclin D1 between the two groups. Further analysis showed that in DGA, the positive expression of KLF4, SP1, and Cyclin D1 were significantly correlated with lymph node metastasis. In AEG, only Cyclin D1 expression was correlated with lymph node metastasis (P<0.05). No correlation was found among the expression of KLF4, SP1, and Cyclin D1 in AEG. In DGA, KLF4 was inversely correlated with SP1 and Cyclin D1 (r=-0.334 and r=-0.341, respectively, P<0.05), and SP1 was positively correlated with Cyclin D1 expression (r=0.340, P<0.05).Conclusion:Different expression patterns and clinicopathological significance of KLF4, SP1, and Cyclin D1 were observed between AEG and DGA, suggesting the putative difference in the carcinogenesis and progression of AEG and DGA.